qgis: loading elevation layers
DESCRIPTION
QGIS: loading elevation layers. Franck Theeten, Royal Museum for central Africa Cabin training 2013. Data format. Elevation data are usually raster data available in 2 formats GRID GeoTIFF ( TIff images file associated to a metadata file giving the position of the image) . - PowerPoint PPT PresentationTRANSCRIPT
QGIS: loading elevation layers
Franck Theeten,Royal Museum for central AfricaCabin training 2013
Data format
• Elevation data are usually raster data available in 2 formats– GRID– GeoTIFF (TIff images file associated to a metadata
file giving the position of the image)
Accessing files
• Free elevation data are available from the STRM (Shuttle Radar Topography Mission) project of the American USGS
• 90M data GeoTIFF can be downloaded on the website of CGIAR :– http://www.cgiar-csi.org/data/srtm-90m-digital-el
evation-database-v4-1
Importing the DEM
• Import the (unzipped) DEM GeoTIFF as raster layer (select the tif file):
Importing the DEM
• You should see a grey zone that still requires the application fo a color scheme
Color scheme
• Right click the properties of the layer
Color Scheme
• Create 20 Classification zones and click classify:
Color scheme
• Bu double-clicking on the three columns, change the value, color and label to the following values (for the exercise)
Color scheme
• Resulting image:
Get information
• To get the information about a specific point, select the active layer in the left menu and click on the button – (also work for shapefile)
Get information
Altitude value in meters